Add Metadata frame-packing=3 for Youtube SBS 3D Video

Hi,
there are options for VR180 and VR360 sequences but no option for 3D sbs video.

Is it possible to add the frame-packing=3 info to the metadata in the export tab so this info is added to the exported video?

At the moment I have to add this metadata with ffmpeg by creating a new video which is a bad solution.

Or is there any metadata editor software which can add this info to a video file?

Thanks for your help!